Abstract

We report a study of the attenuation spectra transformations for a series of Bismuth (Bi) doped silica fibers with various contents of emission-active Bi centers, which arise as the result of irradiation by a beam of high-energy electrons. The experimental data reveal a substantial decrease of concentration of the Bi centers, associated with the presence of Germanium in silica glass, at increasing the irradiation dose (the resonant-absorption bleaching effect in germano-silicate fiber). In contrast, the spectral changes that appear in Bi doped alumino-silicate fiber have through irradiation a completely different character, viz., weak growth of the resonant-absorption peaks ascribed to the Bi centers, associated with the presence of Aluminum in silica glass. These results demonstrating high susceptibility of Bi centers to electron irradiation while opposite routes of the irradiation-induced spectral changes in Bi doped germanate and aluminate fibers seem to be of worth notice for understanding the nature of these centers.

D. L. Griscom, “Self-trapped holes in pure-silica glass: A history of their discovery and characterization and an example of their critical significance to industry,” J. Non-Cryst. Solids 352(23-25), 2601–2617 (2006).
[CrossRef]

D. L. Griscom, “Self-trapped holes in pure-silica glass: A history of their discovery and characterization and an example of their critical significance to industry,” J. Non-Cryst. Solids 352(23-25), 2601–2617 (2006).
[CrossRef]

D. L. Griscom, “Self-trapped holes in pure-silica glass: A history of their discovery and characterization and an example of their critical significance to industry,” J. Non-Cryst. Solids 352(23-25), 2601–2617 (2006).
[CrossRef]

D. L. Griscom, “Self-trapped holes in pure-silica glass: A history of their discovery and characterization and an example of their critical significance to industry,” J. Non-Cryst. Solids 352(23-25), 2601–2617 (2006).
[CrossRef]

(a) Attenuation spectra of Bi doped germano-silicate fiber sample #48 obtained before (dose “0”) and after (doses “2” and “3”) electron irradiation. The spectral area, comprising the resonant-absorption peaks “1” and “2” which attribute Bi centers associated with the presence of Ge and Si in the host glass, is shown. (b) Insight to the spectral area of peak “2” in a vaster scale.

Attenuation spectra of Bi doped alumino-silicate fiber #33 obtained before (curve 1, dose “0”) and after (curve 2, dose “3”) electron irradiation. A part of the spectra is shown where the main resonant-absorption peaks of Bi(Al) centers are observed. Inset highlights the behavior of one of the peaks (@~700 nm) against the irradiation dose.